Self-adjusting contactor for valves



F. W. JOHNSON Filed April 4, 1952 3/) INVENTOR.

BY fZ'd/IkWx/OfiI/JW A TTOR/VE 7-.

SELF-ADJUSTING CONTRACTOR FOR VALVES 20 lg? lg Oct. 25, 1955 UnitedStates Patent SELF-ADJUSTING CONTACTOR FOR; VALVES.

Frank W. Johnson, Kansas City, Mo. Application April 4, iasasensmq.280,588

6 Claims. (Cl. 1-23'-.-90)

This invention relates. toaself-adjusting contactor for poppet-type;valves as used in internal combustion engines and has for, its principalobject to.provide a hydraulic; unit of thischaracter that is readilyapplied toa conventional valve operating mechanism. as. a. single; unitand which involves no alteration of the existing; parts of an. enginewith the exception of shortening thetappetor push rod,

Other objects of the invention are to provide a selfadjusting contactorwhich ispositive in action; is of simple construction and easilyassembled: to form a sealed, selfcontained unit.

In accomplishing these and other objects of, the invention hereinafterpointed out, I haveprovided. improved structure, the preferred formofwhich isillustrated in. the accompanying drawing wherein:

Fig. l is a'vertical sectional view through an engine having the valvegear equipped with a. self-adjusting; con.- tactor constructed inaccordance with the present inventron.

Fig. 2 is an enlarged vertical sectional view of theselfadjustingcontactor.

Fig. 3 is. a perspective view of the working parts of th self-adjustingcontactor shown in disassembled spaced relation.

Fig. 4 is a. horizontal section: through the contactor on the-line 44 ofFig. 2. 7

Referring more in detail to the drawings:

1 designates a conventional type. internal combustion engine having acylinder block 2 containing a piston cham her 3 in which apiston- 4' is.reciprocablymounted for actuation by. a connecting rod 5-and crank shaft6.

The engine also includes a cylinder head 7 having a combustion chamber 8in connection. with the cylinder chamber. The engine illustrated. is ofthe overhead valve type and has exhaust and intake valves, one, ofwhich, is designated 9 for controlling the passageway 10. The valve 9.has a stem 11 that is. slidably mounted, inv av bore 12 in the head 7.The head of. the, valve is retained in position on a seat 13by a coilspring14 having one end engaging a seatingwasher 15 that is securedto.the. stem 11 and the. other end engaging a seat 16 in. the cylinderhead.

The valve 9 is actuated by a rocker arm 17. having one arm. 18 engagingthe end. of the stem. 11 and an arm 19 carrying an adjusting screw 20,which. ordinarily engages the end of a push rod 21. The other end. ofthe push. rod has a ball and socket connection 22. with a plunger 23which is operated by a cam shaft 24. havinga cam. 25.

It is. well known that clearance must beprovidedin. the tappet' portionsof the valve gear to assure. that the'valves seat properly.Consequently, such valve gears are noisy in. operation. In the modernengines, this difficulty is overcome by hydraulic valve lifters. which.are actuated by pressure fluid. from the pressure oiling systems of suchengines. Such valve lifters. are built into. the. engine. at the time:of its construction and are subject tooperational diflicnlties becauseof foreign particles. usually contained in the lubricating oil.

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These difliculties, are overcome through the-present invention byproviding the valve gear with a self-contained, adjusting unit 26 forautomatically taking up clearance and providing silent operation of thevalve gear.

In? the illustrated instance, the unit 26 includes, a cylindricalbody'member 27 having an annular wall 28 which is provided} with, aninternal, annular shoulder 29 for sup- PQItting a spring seating washer30 later described. The lower end of the cylinder body is closed by ahead 31 having an annular shoulder 32. which has a press fit within thecylinder to provide a leak-tightjoint therewith. The head has a. fixedpiston element 33 that projects into the cylinder and which is ofsmaller diameter than the inner diameter of the cylinder to leave anannular passageway 34 therebetweem The fixed piston 33 is of cylindricalshape and has annular groovev 35 formed in the periphery thereof to seatpiston rings. 36 which form a. seal with. a movable piston element 37.The inner end 38 of the stationary piston is substantially flat and theaxial center thereof is provided with a bore 39: to accommodate a pilot40 on a valve plunger 41' later described. The outer, lower end of thecylinder headv 31 has an axial recess 42' which is adapted toreceive theupper end of the push rod; 21 as best shown in Fig. 2.

The movable piston. element 37 includes a cylindrical skirt.- portion.43; that is. sleeved over the stationary piston element 33 and has ahead. 44' to cooperate with the inner end of the fixed piston in forminga pressure chamber 45' of variable capacity, depending upon the positionof the movable piston relative to thefixed piston.

A suitable liquid is admitted intoand discharged from the pressurechamber 45, through an axial port 46 in the head 44: of the movablepiston 37, and the periphery of the port forms a seat 47 for a beveledannular valve face 48 on the valve plunger 41.

The head 44: of the movable piston 37 has: a laterally extending annularperiphery 49* that is loosely positioned Within: the inner wall. of thecylinder to form an annular seat 50; for one endv of a coil spring 51'that encircles the skirt portion: of the movable piston and has itsother end engaging a seat 52' on the. cylinder head 31 immediatelyencircling the fixed. piston 33 (shown in Fig. 2).

The valve plunger 41 includes a stemportion 53 that projects through ahead 54.which closes the opposite end of-the cylinder. Thehead 54- hasan annular flange portion. 55 which hasa pressed fit over that end ofthe cylinder to form a leak-tight joint and to retain a washer 56 in:engagement with a packing ring 57 that is inset within a. counterbore58' on the inner side of the head and encircling anv opening 59? throughwhich the end of the plunger projects. Thepacking ring thus forms aliquidtight seal about the stem of the plunger and prevents leakage ofthe operating liquid 60 from the cylinder during actuation ofthevalvegear;

Thevalve plunger moves through an opening 30. in the spring seat 30 and;is lifted from itsseat 47 during a portion of the operation of the,valve gear by-means of a coil spring 61 seating on the washer 30 andhaving the other end engaging asplit washer 6 2- that' is, retained in.an annular groove 63. oi the plungerstern. (see. Figs. 2 and 3). The,washer 307 has a. plurality of. openings 64 by which fluid is.transferred toa-nd from the respective, sides or the seating washerthereby providingmaxi'rnum: fluid capacity for a given size mechanism.

The pilot recess. is vented into the pressure chamber through a port 65of the pilot so as; to avoid trapping of liquid under the pilot.

The outer end of thevalve plunger is provided with a conical seat 66 forreceiving the conical end. 67 of the adjusting screw 20, previouslydescribed.

In assembling the parts of the self-adjusting contactor,

the piston rings 36 of the fixed piston element 33 are inserted in thegrooves 35 thereof. The coil spring 51 is then sleeved over the fixedpiston element 33 to engage the seat 52. The movable piston element 37is applied by sliding the skirt portion 43 thereof between the coilspring 51 and the fixed piston element 33. The seating washer 30 isinserted through the opposite end of the cylinder. The split washer 62is then slid in the groove 63 of the valve plunger 41, and the spring 61is sleeved over the pilot end 40 of the plunger 41, after which thevalve plunger 41 is moved into position with the pilot 40 passingthrough the opening 30 in the seating washer 30 and through the valveport 46 of the movable piston element 37, the pilot 40 sliding into thepilot recess 39 to provide a guide in retaining axial alignment of thevalve face 48 of the plunger with the valve seat 47 in the head of themovable piston element 37.

All of the space within the cylinder is then filled to the level of theupper end thereof with a lubricating oil 60.

The washer 56 is then applied to the open end of the cylinder, and thehead 54 carrying the packing ring 57 is sleeved over the projecting end53 of the valve plunger 41 with the skirt 55 being pressed tightly overthe wall of the cylinder to complete the assembly.

In fitting the adjuster to the valve gear of an existing engine, asuificient amount of the push rod 21 is cut off so that when the upperend thereof is engaged in the axial recess 42, there is SllffiClCHt roomto accommodate the adjuster below the arm 19 of the valve rocker 17. Theadjusting screw 20 is then moved into position so that the conical end67 thereof engages in the recess 66 of the valve plunger 41 to take upall of the slack in the valve gear. After the slack has been taken up,the adjusting screw 20 is given an additional partial turn. Thismaintains a positive seat between the valve plunger 41 and movablepiston element 37 against action of the spring 51.

When the plunger 23 is engaging the low portion of the cam shaft 24, thespring 61 lifts the valve plunger 41 so that liquid flows through theport 46 to fill the pressure chamber 45. When the plunger and push rodare lifted by the high lobe portion 25, the push rod 21 lifts the entireunit 26. The pressure of the valve plunger 41 acting against the rockerarm seats the face 48 of the valve plunger against the seat 47 to trapthe liquid in the pressure chamber 45 so that movement of the valve iseffected through the liquid trapped in the pressure chamber 45 whicheliminates the slack that produces noise in conventional valve gear.

While the invention is particularly adapted for use as an attachment forvalve gear of existing engines, it is obvious that it is also suitablefor use in the valve gear of any internal combustion engine.

While I have particularly described the invention as applied to anoverhead type of valve gear, it is obvious that the complete unit may beinserted between the valve stem and tappet of any L head type engine byshortening the valve stem.

What I claim and desire to secure by Letters Patent is:

1. A self-adjusting contactor for insertion between an operating memberand an operated member in a valve gear for a poppet type valve includinga cylindrical member, a fixed piston closing one end of the cylindricalmember and having a recess to receive the operating member therein andhaving a piston element extending into the cylindrical member, a movablepiston element having a skirt portion slidable over the first namedpiston element to form a variable capacity pressure chambertherebetween, the movable piston element having a port in connectionwith the pressure chamber, a head closing the other end of thecylindrical member, a plunger having a valving face normally closingsaid port during actuation of the operating member to trap liquid in thepressure chamber for taking up any slack in the valve gear and having anend projecting through the head for connection with the operated member,and

spring means for moving the plunger from closing relation with the portand maintaining said pressure chamber when slack occurs in the valvegear to effect filling of said pressure chamber upon closing of thepoppet valve by said valve gear.

2. A self-adjusting contactor for insertion between an operating memberand an operated member in a valve gear of a poppet type valve includinga cylindrical member, a fixed piston closing one end of the cylindricalmember and having a recess to receive the operating member and having apiston element extending into the cylindrical member, a movable pistonelement having a skirt portion slidable over the first named pistonelement to form a variable capacity pressure chamber therebetween, saidcylindrical member having an inner shoulder spaced from the movablepiston element, a spring seat on said shoulder and having an axialopening registering with a port in the movable piston element, a headclosing the other end of the cylindrical member, a plunger having avalving end normally closing said port during actuation of the operatingmember to trap liquid in the pressure chamber for taking up any slack inthe valve gear and having an end projecting through said head to engagethe operated member, a spring having one end seated on the spring seat,resilient means engaging the movable piston element to maintain thepressure chamber and a spring seat carried by the plunger for engagingthe other end of the spring to lift the plunger for passing liquid intothe pressure chamber when slack tends to occur in the valve gear.

3. A self-adjusting contactor for insertion between an operating memberand an. operated member in a valve gear of a poppet type valve includinga cylindrical member, a fixed piston closing one end of the cylindricalmember and having a recess to receive the operating member and having apiston element extending into the cylindrical member, a movable pistonelement having a skirt portion telescoping the first named pistonelement to form a variable capacity pressure chamber therebetween, saidcylindrical member having an inner shoulder spaced from the movablepiston element, a spring seat on said shoulder and having an axialopening registering with a port in the movable piston element, a headclosing the other end of the cylindrical member, a plunger hav ing avalving face normally closing said port during actuation of theoperating member to trap liquid in the pressure chamber for taking upany slack in the valve gear and having an end extending through saidhead to engage the operated member, resilient means engaging the movablepiston element to maintain the pressure chamber, a spring having one endseated on the spring seat, a spring seat carried by the plunger forengaging the other end of the spring to effect lifting of the plungerfor passing liquid into the pressure chamber when slack tends to occurin the valve gear, and packing carried by said head for sealing aboutthe plunger.

4. A self-adjusting contactor for insertion between an operating memberand an operated member in a valve gear of a poppet type valve includinga cylindrical member, a fixed piston closing one end of the cylindricalmember and having a recess to receive the operating member and having apiston element extending into the cylindrical member, a movable pistonelement having a skirt portion telescoping the first named pistonelement to form a variable capacity pressure chamber therebetween, saidcylindrical member having an inner shoulder spaced from the movablepiston element, a spring seat on said shoulder and having an axialopening registering with a port in the movable piston element, a headclosing the other end of the cylindrical member, a plunger having avalving face normally closing said port during actuation of theoperating member to trap liquid in the pressure chamber for taking upany slack in the valve gear and having an end extending through saidhead to engage the operated member, resilient means engaging the movablepiston element to maintain the pressure chamber, a spring having one endseated on the spring seat, a spring seat carried by the plunger forengaging the other end of the spring to effect lifting of the plungerfor passing liquid into the pressure chamber when slack tends to occurin the valve gear, packing carried by said head for sealing about theplunger, and a pilot at the other end of the plunger slidably mounted ina recess of the fixed piston element.

5. A self adjusting contactor adapted for insertion between an actuatedand an actuating member of a poppet type valve gear including a memberhaving support on the actuating member and having a liquid containingchamber, movable piston means in said liquid containing chamber, one ofsaid piston means having a peripherial portion slidable in sealingcontact with the other piston means to provide a pressure chamberbetween said means, the movable piston means having a port therein inconnection with the pressure chamber, resilient means engaging themovable piston means and seated on a part of said member having theliquid containing chamber to maintain the pressure chamber between thepiston means, a plunger having a valving face for closing the port inthe movable piston means and adapted to engage the actuated member onthe plunger closing side of said port, and a spring having one end fixedrelative to the member having the liquid containing chamber, and theother end engaging a part of the plunger to lift the plunger when slacktends to form in the valve gear to allow liquid to flow in the chamberto take up said slack upon reseating of the valving face of the plunger.

6. A self adjusting contactor adapted for insertion between an actuatedand an actuating member of a poppet type valve gear including a memberhaving support on the actuating member and having a liquid containingchamber, relatively movable piston elements carried within said liquidcontaining chamber and having heads, one of said piston elements havinga skirt encircling the head of the other piston element to provide apressure chamber between the heads of said elements and to provide asliding seal for the pressure chamber, one of the piston elements havinga port in connection with the pressure chamber, resilient means urgingthe piston elements apart to maintain said pressure chamber and aclearance between the heads of the fixed and movable piston elements toallow for action of the valve gear, a plunger having a valve portion forclosing said port and adapted to engage the actuated member on theplunger closing side of said port, and a spring having one end fixedrelative to the member having the liquid containing chamber and theother end engaging a part of the plunger to lift the plunger when agreater amount of clearance tends to form in the valve gear to allowliquid to flow through said port into the pressure chamber to take upslack upon reseating of the valve portion of the plunger.

References Cited in the file of this patent UNITED STATES PATENTS

